System and Method for Determining a Resource Selection Technique

ABSTRACT

A method for vehicle-to-everything (V2X) communication in a wireless network, the method includes determining, by a first User Equipment (UE), a V2X carrier load in a coverage area of a Base station (BS), and transmitting, by the first UE, a data message over an air interface using either a random resource selection technique or a resource sensing multiple access technique based on the V2X carrier load in the coverage area of the BS.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of U.S. Provisional Application No.62/294,541, filed Feb. 12, 2016 entitled “System and Method forDetermining a Random Access Method,” which is hereby incorporated byreference herein as if reproduced in its entirety.

TECHNICAL FIELD

The present invention relates to a system and method for wirelesscommunications, and, in particular embodiments, to a system and methodfor determining a resource selection technique.

BACKGROUND

3rd Generation Partnership Project (3GPP) is currently standardizingvehicle-to-everything (V2X) and vehicle-to-vehicle (V2V) communicationfor Long Term Evolution (LTE) and 5th Generation (5G) networks. Toimprove communication across these devices, it is generally desirable toselect communication methods appropriate to the conditions of thenetwork to reduce network congestion and latency, eliminateinconsistencies, and/or promote fairness in resource allocation.

SUMMARY

Technical advantages are generally achieved, by embodiments of thisdisclosure which describe systems and methods for determining a resourceselection technique.

In accordance with an embodiment, a method for vehicle-to-everything(V2X) communication in a wireless network, the method includesdetermining, by a first User Equipment (UE), a V2X carrier load in acoverage area of a Base station (BS), and transmitting, by the first UE,a data message over an air interface using either a random resourceselection technique or a resource sensing multiple access techniquebased on the V2X carrier load in the coverage area of the BS.

In accordance with yet another embodiment, a method forvehicle-to-everything (V2X) communication in a wireless network, themethod includes determining, by a first User Equipment (UE), a length ofa V2X data message, and transmitting, by the first UE, the V2X datamessage over an air interface using either a random resource selectiontechnique or a resource sensing multiple access technique based on thelength of the V2X data message.

In accordance with yet another embodiment, a method forvehicle-to-everything (V2X) communication in a wireless network, themethod includes determining, by a Base Station (BS), a V2X carrier loadin a coverage area of the BS, determining, by the BS, whether a randomresource selection technique or a resource sensing multiple accesstechnique should be used for transmissions in the coverage area of theBS based on the V2X carrier load of the coverage area, and transmitting,by the BS, a control message to at least one UE, the control messageinstructing the at least one UE to perform transmissions using eitherthe random resource selection technique or the resource sensing multipleaccess technique.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawing, in which:

FIG. 1 is a diagram of a network for communicating data;

FIG. 2 is a diagram of a general V2X communication network;

FIG. 3 is a flowchart of an embodiment method for transmitting data overa V2X network using either a random resource selection or resourcesensing multiple access technique;

FIG. 4 is a flowchart of another embodiment method for transmitting dataover a V2X network using either a random resource selection or resourcesensing multiple access technique;

FIG. 5 is a flowchart of an embodiment method for instructing a UE toperform V2X transmissions using either a random resource selection orresource sensing multiple access technique;

FIG. 6 is a diagram of an embodiment of a resource pool structure;

FIG. 7 is a flowchart of an embodiment method for determining theaverage resource occupancy in a V2X network;

FIG. 8 is a graph of throughput curves for transmissions using variousgrant-free access protocols;

FIG. 9 is a graph of autonomous UE transmissions of LTE-based traffic at140 km/h speeds;

FIG. 10 is a flowchart of yet another embodiment method for transmittingdata over a V2X network using either a random resource selection orresource sensing multiple access technique;

FIG. 11 is a flowchart of yet another embodiment method for transmittingdata over a V2X network using either a random resource selection orresource sensing multiple access technique;

FIG. 12 is a flowchart of another embodiment method for instructing a UEto perform V2X transmissions using either a random resource selection orresource sensing multiple access technique;

FIG. 13 is a flowchart of an embodiment method for transmitting dataover a V2X network using either a random resource selection or resourcesensing multiple access technique;

FIG. 14 is a block diagram of an embodiment processing system forperforming methods described herein; and

FIG. 15 is a block diagram of a transceiver adapted to transmit andreceive signaling over a telecommunications network.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The structure, manufacture, and use of embodiments are discussed indetail below. It should be appreciated, however, that this disclosureprovides many applicable inventive concepts that can be embodied in awide variety of specific contexts. The specific embodiments discussedare merely illustrative of specific ways to make and use the invention,and do not limit the scope of the invention.

As used herein, the term “Vehicle-to-Everything (V2X) communication”refers to wireless communication between a vehicle and another device,including uplink and/or downlink transmissions between a vehicle and aBase Station (BS) as well as vehicle-to-vehicle (V2V) communicationsbetween two or more vehicles.

The present disclosure will be described with respect to exampleembodiments in Long Term Evolution (LTE)-based V2X communicationnetworks. Embodiment V2X resource selection may be implemented instandards compliant communications systems, such as those compliant withthe Institute of Electrical and Electronic Engineers (IEEE) 802.11and/or other technical standards, as well as non-standards compliantcommunication systems. As used herein, the term “network” refers to anycollection of two or more devices that communicate directly orindirectly with one another, including those in which a user-side device(e.g., a User Equipment) communicates directly with a network-sidedevice (e.g., a base station), those in which user-side devicescommunicate indirectly with one another via network-side-devices, andthose in which user-side devices communicate indirectly with one anotherwithout relaying the communications through network-side devices. Otherexamples are possible, such as when network-side devices communicatedirectly with one another.

Wireless vehicle communication provides numerous benefits, not limitedto, improvements in safety in the form of forward collision warning androad work notification, energy efficiency in the form of enhanced routeselection, and time saving and convenience in the form of real timeroute correction. One challenge in V2X communication is that handoversoccur quite frequently, which makes it difficult to efficiently scheduleresources for transmission from the vehicles to BSs or to othervehicles. One alternative is for the vehicles to perform grant-freeuplink transmission using either resource sensing multiple accesstechnique or a random resource selection technique.

Resource sensing multiple access techniques seek to avoid collisionsbetween grant-free transmissions from different User Equipments (UE)s byrequiring the UEs to sense a grant-free resource for a sensing periodprior to transmitting a data message over the grant-free resource. Ifthe UE senses a transmission from another UE during the sensing period,then the UE either defers transmission of the data message until thegrant-free resource becomes free or switches to a different grant-freeresource. Carrier sensing multiple access (CSMA) is a widely usedresource sensing multiple access technique.

Random resource selection techniques avoid the latency associated withresource sensing multiple access technique by allowing the UEs totransmit a data message over a grant-free resource immediately withoutwaiting for expiration of a sensing period. Resource sensing multipleaccess techniques and random resource selection techniques providedifferent levels of performance (e.g., throughput, reliability, etc.) indifferent scenarios. Accordingly, techniques for selecting between thetwo are needed for V2X communication. Embodiments of this disclosureselect between resource sensing multiple access technique and randomresource selection technique based on a V2X carrier load in a coveragearea of a BS and/or a length of a V2X data message to be transmitted bythe UE. The V2X carrier may be a standalone carrier on a V2Xcommunication dedicated channel or on a channel shared with cellularcommunications.

In an embodiment, the V2X carrier load can be determined by a UEaccording to an energy level of one or more subcarriers associated witha BS. In another embodiment, the UE can monitor a control channel todetermine a number of grant-free transmissions performed by neighboringUEs and determine the V2X carrier load according to the number ofgrant-free transmissions performed by the neighboring UEs. In theseembodiments, the UE sends a data message using the random resourceselection technique when the V2X carrier load is less than a lower loadthreshold or greater than an upper load threshold, and sends the datamessage using the resource sensing multiple access technique when theV2X carrier load is in-between the lower load threshold and the upperload threshold. In another embodiment, a BS determines the V2X carrierload, selects the appropriate access technique based on the V2X carrierload, and instructs the UEs to use the selected access technique viadownlink control signaling (e.g., a broadcast message, etc.).

In another embodiment, a UE determines a length of a V2X data messageand uses a random resource selection technique to transmit the V2X datamessage when the length of the V2X data message is less than a datalength threshold, and uses a resource sensing multiple access techniqueto transmit the V2X data message when the length of the V2X data messageexceeds the data length threshold. The upper and lower load thresholds,and/or data length threshold may be determined by the UE or a BS.

In one embodiment, the data length and/or upper and lower loadthresholds are a priori information of the UE, or otherwise determinedby the UE without a pre-configured protocol, such as load prediction. Inone embodiment, the data length and/or upper and lower load threshold istransmitted by the BS to the UE.

FIG. 1 is diagram of a network 100 for communicating data. The network100 includes a BS no having a coverage area 101, a plurality of UEs 120,and a backhaul network 130. As shown, the BS no establishes uplink(dashed line) and/or downlink (dotted line) connections with the UEs120, which serve to carry data from the UEs 120 to the BS no andvice-versa. Data carried over the uplink/downlink connections mayinclude data communicated between the UEs 120, as well as datacommunicated to/from a remote-end (not shown) by way of the backhaulnetwork 130. As used herein, the term “base station (BS)” refers to anycomponent (or collection of components) configured to provide wirelessaccess to a network, such as an enhanced Node B (eNB), atransmit/receive point (TRP), a macro-cell, a femtocell, a Wi-Fi AccessPoint (AP), and other wirelessly enabled devices. BSs may providewireless access in accordance with one or more wireless communicationprotocols, e.g., 5th generation new radio (5G_NR), LTE, LTE advanced(LTE-A), High Speed Message Access (HSPA), Wi-Fi 802.11a/b/g/n/ac, etc.As used herein, the term “UE” refers to any component (or collection ofcomponents) capable of establishing a wireless connection with a BS,such as a mobile device, a mobile station (STA), and other wirelesslyenabled devices. In some embodiments, the network 100 may includevarious other wireless devices, such as relays, low power nodes, etc.

FIG. 2 is a diagram of a V2X network 200. The V2X wireless network 200includes a BS 230 and UEs 210, 220. The UE 210 transmits a data messageover an air interface in a coverage area of a BS 230. The air interfacemay be a sidelink 221 between the UE 210 and the UE 220 or a wirelessconnection 231 between the UE 210 and the BS 230. The UE 210 maytransmit the data message over the air interface using either a randomresource selection technique or resource sensing multiple accesstechnique.

In one embodiment, the UE 210 selects either the random resourceselection technique or the resource sensing multiple access techniquebased on a V2X carrier load in the coverage area 201 of the BS 230. TheUE 210 may determine the V2X carrier load by measuring an energy levelon one or more subcarriers associated with the BS 230. Alternatively,the UE 210 may determine the V2X carrier load based on the number ofgrant-free transmissions performed by neighboring UEs, e.g., the UE 220and/or other UEs in the coverage area 201 of the BS 230. For example,the UE 210 may monitor a control channel to determine a number ofgrant-free transmissions performed by neighboring UEs. The controlchannel may be established over one or more V2V interfaces between UEsin the coverage area 201 of the BS 230, such as over the V2V interface221 between the UE 210 and the UE 220 as well as V2X interface betweenthe UE 210 and other neighboring UEs. UEs may transmit a message overthe control channel every time a grant-free transmission is performed,thereby allowing other UEs in the network to gauge, or otherwiseestimate, the V2X carrier load based on the number of messages detectedin the channel.

In yet another embodiment, the BS 230 transmits a control message to theUE 210 instructing the UE 210 to perform data transmissions using eitherthe random resource selection technique or the resource sensing multipleaccess technique. The BS 230 may transmit the control message indirectlyto the UE 210 via an intermediate device. The intermediate device may beanother UE (e.g., the UE 220) or another BS. Alternatively, the BS 230may transmit the control message directly to the UE 210 without thewireless connection 231.

FIG. 3 is a flowchart of an embodiment method 300 for transmitting dataover a V2X network using either a random resource selection or resourcesensing multiple access technique in accordance with a V2X carrier load,as may be performed by a UE. At step 310, the UE determines the V2Xcarrier load in a coverage area of a BS. At step 320, the UE comparesthe V2X carrier load with an upper and lower load threshold. If the V2Xcarrier load is less than the lower load threshold or greater than theupper load threshold, then the UE transmits the V2X data message over anair interface using the random resource selection technique at step 330.Alternatively, if the V2X carrier load is in-between the upper and lowerload thresholds, then the UE transmits the V2X data message over the airinterface using the resource sensing multiple access technique at step340.

FIG. 4 is a flowchart of another embodiment method 400 for transmittingdata over a V2X network using either a random resource selection orresource sensing multiple access technique in accordance with a V2X datamessage length, as may be performed by a UE. At step 410, the UEdetermines the length of the V2X data message. At step 420, the UEcompares the length of the V2X data message with a data lengththreshold. If the length of the V2X data message is less than the datalength threshold, then the UE transmits the V2X data message over an airinterface using the random resource selection technique at step 430. Onthe other hand, if the length of the V2X data message is greater thanthe data length threshold, then the UE transmits the V2X data messageover the air interface using the resource sensing multiple accesstechnique at step 440.

FIG. 5 is a flowchart of an embodiment method 500 for instructing a UEto perform V2X transmissions using either a random resource selection orresource sensing multiple access technique, as may be performed by a BS.At step 510, a BS determines a V2X carrier load in a coverage area ofthe BS. At step 520, the V2X carrier load is compared to an upper andlower load threshold. If the V2X carrier load in the coverage area ofthe BS is less than the lower load threshold or greater than the upperload threshold, the BS transmits a control message to the UE thatinstructs the UE to perform a data transmission using the randomresource selection technique at step 530. Alternatively, if the V2Xcarrier load in the coverage area of the BS is in-between the upper andlower load thresholds, the BS transmits a control message to the UE thatinstructs the UE to perform a data transmission using the resourcesensing multiple access technique at step 540. The BS may transmit thecontrol message indirectly to the UE via an intermediate device. Theintermediate device may be another UE or another BS. Alternatively, theBS may transmit the control message to the UE without another BS oranother UE.

FIG. 6 is a diagram of an embodiment resource pool structure 600 showingboth data pools 620 and scheduling assignment (SA) pools 610. In someembodiments, where the V2V traffic may have a known periodicity and aconstant message size, a correlation exists between the number of SAstransmitted and the load around a UE. On each SA pool subframe where aUE does not transmit, it attempts to decode the transmitted downlinkcontrol information (DCI). The UE can determine the number of SAs it candecode over a number of subframes of the SA pool to average randomfluctuations. The determined average resource occupancy (G) is a crudemeasurement of the load.

FIG. 7 is a flowchart of an embodiment method 700 for determining theaverage resource occupancy in a V2X network, as may be performed by aUE. At step 710, the UE obtains the resource pool configuration. Theresource pool configuration may be sent, for instance, in a systeminformation block (SIB) message and refer to the carrier from where theSIB is sent (shared carrier) or a dedicated carrier. In an embodiment,if the UE is in coverage, the pools may be obtained from the eNB byeither dedicated or common radio resource control (RRC) signaling. Inanother embodiment, if the V2V signaling mechanism is the same as fordevice-to-device (D2D), the pools can be obtained from SIB18/19. In aseparate embodiment, if the UE is out-of-coverage, the UE may rely onpre-configured pools known to the UE. At step 720, the UE determines thenumber of SAs it can decode over a number of subframes of the SA pool toaverage random fluctuations. The UE then determines the average resourceoccupancy load (G), which is a crude measurement of the load at step730. Alternatively, the resource occupancy could be measured by othermeans, such as performing energy measurements on the transmissionresources comprising the V2X carrier.

The process of determining the resource occupancy load can be furtherrefined by the following:

Firstly, in an embodiment, the length of the averaging window can bespeed dependent. For instance, in stop/go traffic, the averaging windowcan be different from fluid traffic conditions on a highway.

In an embodiment, where the V2V traffic includes a periodic and anon-periodic component, the average load occupancy may be measured onthe SAs for periodic messages only.

In an embodiment, where the average load occupancy indicates the averageload on the SA pool, when the message size of a periodic V2Vtransmission is roughly known, and when the UE knows the size of thedata pool for V2V transmission, the UE can use this information todetermine the average load on the V2V data pool (for the periodiccomponent; for aperiodic, same caveat as before applies).

In an embodiment, where the SA and/or data message is repeated, thenumber of repetitions can be taken into account for the determination ofthe average load occupancy.

In an embodiment, where there is a one-to-one association between SA anddata, the UE can measure data occupancy, SA occupancy, or both and notjust rely on the SA measurement.

In an embodiment further refinements can be obtained by also includinge.g., reference signal received power (RSRP) or reference signalreceived quality (RSRQ)-like measurements on SAs, or taking into accountthe value of the power control command in the SA.

Lastly, in an embodiment, a UE can transmit a bitmap to measure how manyUEs can listen to this particular UE, where typically the knownoccupancy factor for the UE is limited to the number of UE's it canlisten to. Given that traffic can be highly variable by nature, thereare cases where there could be significant differences between the twomeasures. One way to obtain the number of UE's a UE can listen to, is tohave each UE indicate resources it can correctly decode. This can bedone by appending a bitmap message to a V2V transmission, wherein eachbit of the bitmap represents a particular SA resource. For instance,transmitting a ‘1’ would indicate that the message corresponding to thatparticular SA was successfully received. Transmitting a ‘0’ wouldindicate that it was not. This bitmap appendage technique increases theV2V message size, and thus the overhead. This can be compensated byhaving only a fraction of all the UEs adding this bitmap. Anotheralternative is to only occasionally add this bitmap at known locations.Another advantage of this bitmap appendage technique is by adjusting thenumber of retransmissions of a given message to prevent unnecessarycollisions. This technique can be further improved, although at theprice of higher complexity. Specifically, a given UE can also decode allthe data messages, and keep track of them to determine the actual UE maparound it. This way, knowing the message periodicity and message size,the UE can know the average occupancy.

FIG. 8 is a graph of throughput curves for transmission using variousgrant-free access protocols (ALOHA, Carrier sense multiple access(CSMA), etc.). The graphs show that the curves are generallydome-shaped. There is a ramping up where the throughput increases withload (low collision regime) and after a peak, the throughput decreaseswith load, and asymptotically reaches zero (high collision regime).

FIG. 9 is a graph of autonomous UE transmissions of LTE-based V2Xtraffic at 140 km/h speeds. As shown in the curves, it is observed thatsensing 910 is more beneficial (sensing+reservation curve) than othertechniques 920. This is a case where the resource utilization isrelatively low, and sensing avoids collisions. At lower speeds,throughput is decreasing and similar gains are not observed.

FIG. 10 is a flowchart of yet another embodiment method 1000 fortransmitting data over a V2X network using either a random resourceselection or resource sensing multiple access technique, as may beperformed by a fully autonomous UE (no network involvement). Theembodiment is limited to a local view of the network environment anddoes not utilize the resources of a BS. At step 1010, the UE obtains aload threshold (Th) through pre-configuration. The embodiment methodrequires defined specifications for UE behavior and a minimumstandardization effort. At step 1020, the UE determines the V2X carrierload. At step 1030, the UE compares the V2X carrier load with thepre-configured load threshold. Based on this comparison, if the V2Xcarrier load in the coverage area of a BS is less than the loadthreshold, then the UE transmits the V2X data message over an airinterface using the random resource selection technique at step 1040.Alternatively, if the V2X carrier load in the coverage area of a BS isgreater than the load threshold, then the UE transmits the V2X datamessage over the air interface using the resource sensing multipleaccess technique at step 1050. For example, the UE may detect anisolated hot spot in a cell (traffic jam) and chose against resourcesensing multiple access method.

FIG. 11 is a flowchart of yet another embodiment method 1100 fortransmitting data over a V2X network using either a random resourceselection or resource sensing multiple access technique, as may beperformed by a UE and an eNB. In this embodiment, the UE follows thesame process as an autonomous UE; with the exception that the UE mayreceive the threshold value from the eNB 1110 instead of having itpre-configured 1010. In this embodiment, the signal messaging used tosend the threshold value would typically be via a SIB, but a dedicatedRRC message, a physical layer message (e.g., DCI), or the like can alsobe used. At step 1120, the UE determines the V2X carrier load. At step1130, the UE compares the V2X carrier load with the load thresholdreceived from the eNB. Based on this comparison, if the V2X carrier loadin the coverage area of the eNB is less than the load threshold, thenthe UE transmits the V2X data message over an air interface using therandom resource selection technique at step 1140. Alternatively, if theV2X carrier load in the coverage area of the eNB is greater than theload threshold, then the UE transmits the V2X data message over the airinterface using the resource sensing multiple access technique at step1150.

FIG. 12 is a flowchart of another embodiment method 1200 for instructinga UE to perform V2X transmissions using either a random resourceselection or resource sensing multiple access technique, as may beperformed by an eNB. At step 1210, the eNB probes the UE to report theV2X carrier load in a coverage area of the eNB. At step 1220, the eNBreceives the V2X carrier load from the UE. At step 1230, the eNBdetermines if the UE should use the random resource selection techniqueor the resource sensing multiple access technique to transmit V2X datamessages. At step 1240, the eNB sends a control message to the UE toinform the UE of the selected technique.

FIG. 13 is a flowchart of an embodiment method 1300 for transmittingdata over a V2X network using either a random resource selection orresource sensing multiple access technique, as may be performed by a UE.At step 1310, the UE receives a request from an eNB to send the V2Xcarrier load to the eNB. The request from the eNB to measure and sendback the V2X carrier load could be included in a DCI or sent in a RRCdedicated message. The message may include the average duration window,or other parameters needed to perform the measurement (e.g., CQIthreshold to indicate which resource is considered as occupied or not).At step 1320, the UE sends the V2X carrier load to the eNB. The UE mayreport the V2X carrier load in a RRC message, in a media access control(MAC) message, or in a physical layer message, similar to channelquality indicator (CQI). In this instance, a new physical uplink controlchannel (PUCCH) format may be needed. At step 1330, the UE receives theappropriate resource selection technique determined by the eNB in theform of a control message. The eNB may inform the UE of the selectedtechnique in a dedicated RRC message, or in a SIB-type message.

FIG. 14 is a block diagram of an embodiment processing system 1400 forperforming methods described herein, which may be installed in a hostdevice. As shown, the processing system 1400 includes a processor 1410,a memory 1420, and interfaces 1430, 1440, and 1450, which may (or maynot) be arranged as shown in the figure. The processor 1410 may be anycomponent or collection of components adapted to perform computationsand/or other processing related tasks. The memory 1420 may be anycomponent or collection of components adapted to store programmingand/or instructions for execution by the processor 1410. In anembodiment, the memory 1420 includes a non-transitory computer readablemedium. The interfaces 1430, 1440, and 1450 may be any component orcollection of components that allow the processing system 1400 tocommunicate with other devices/components and/or a user. For example,one or more of the interfaces 1430, 1440, and 1450 may be adapted tocommunicate data, control, or management messages from the processor1410 to applications installed on the host device and/or a remotedevice.

In another embodiment, one or more of the interfaces 1430, 1440, and1450 may be adapted to allow a user or user device (e.g., personalcomputer (PC), etc.) to interact/communicate with the processing system1400. The processing system 1400 may include additional components notdepicted in the figure, such as long term storage (e.g., non-volatilememory, etc.).

In another embodiment, the selection process is based on UE speed aloneor in combination with the methods described in the above embodiments.The rationale is that if the UE is moving at a relatively fast speed,what is sensed at a given time will be quickly obsolete and sensing canbe a poor choice. Thus, at high speed a UE might be better offperforming a different method. In an embodiment, the UE computes anindication of its speed. Once the indication of the speed is obtained,it is compared to a speed threshold that can be pre-configured orobtained from the network. The resource selection technique is thenselected based on the speed and its relation to the speed threshold.

In the embodiment above, the speed can be the instantaneous speedaveraged over a time window, the maximum instantaneous UE speed over atime window, and the like. The instantaneous speed may be obtained froma satellite system (e.g., Global Navigation Satellite System (GNSS)),measurements on pilot signals, and the like. The indication of the speedcan be based on absolute speed or relative speed measurement.

In some embodiments, the processing system 1400 is included in a networkdevice that is accessing, or otherwise part of, a telecommunicationsnetwork. In one example, the processing system 1400 is in a network-sidedevice in a wireless telecommunications network, such as a BS, a relaystation, a scheduler, a controller, a gateway, a router, an applicationsserver, or any other device in the telecommunications network. In otherembodiments, the processing system 1400 is in a user-side deviceaccessing a wireless telecommunications network, such as a mobilestation, a user equipment (UE), a personal computer (PC), a tablet, awearable communications device (e.g., a smartwatch, etc.), or any otherdevice adapted to access a telecommunications network. In someembodiments, one or more of the interfaces 1430, 1440, and 1450 connectthe processing system 1400 to a transceiver adapted to transmit andreceive signaling over the telecommunications network.

FIG. 15 is a block diagram of a transceiver 1500 adapted to transmit andreceive signaling over a telecommunications network. The transceiver1500 may be installed in a host device. As shown, the transceiver 1500comprises a network-side interface 1510, a coupler 1520, a transmitter1530, a receiver 1540, a signal processor 1550, and a device-sideinterface 1560. The network-side interface 1510 may include anycomponent or collection of components adapted to transmit or receivesignaling over a wireless telecommunications network. The coupler 1520may include any component or collection of components adapted tofacilitate bi-directional communication over the network-side interface1510. The transmitter 1530 may include any component or collection ofcomponents (e.g., up-converter, power amplifier, etc.) adapted toconvert a baseband signal into a modulated carrier signal suitable fortransmission over the network-side interface 1510. The receiver 1540 mayinclude any component or collection of components (e.g., down-converter,low noise amplifier, etc.) adapted to convert a carrier signal receivedover the network-side interface 1510 into a baseband signal. The signalprocessor 1210 may include any component or collection of componentsadapted to convert a baseband signal into a data signal suitable forcommunication over the device-side interface(s) 1560, or vice-versa. Thedevice-side interface(s) 1560 may include any component or collection ofcomponents adapted to communicate data-signals between the signalprocessor 1550 and components within the host device (e.g., theprocessing system 1400, local area network (LAN) ports, etc.).

The transceiver 1500 may transmit and receive signaling over any type ofcommunications medium. In some embodiments, the transceiver 1500transmits and receives signaling over a wireless medium. For example,the transceiver 1500 may be a wireless transceiver adapted tocommunicate in accordance with a wireless telecommunications protocol,such as a cellular protocol (e.g., long-term evolution (LTE), etc.), awireless local area network (WLAN) protocol (e.g., Wi-Fi, etc.), or anyother type of wireless protocol (e.g., Bluetooth, near fieldcommunication (NFC), etc.). In such embodiments, the network-sideinterface 1510 comprises one or more antenna/radiating elements. Forexample, the network-side interface 1510 may include a single antenna,multiple separate antennas, or a multi-antenna array configured formulti-layer communication, e.g., single input multiple output (SIMO),multiple input single output (MISO), multiple input multiple output(MIMO), etc. Specific processing systems and/or transceivers may utilizeall of the components shown, or only a subset of the components; andlevels of integration may vary from device to device.

While this invention has been described with reference to illustrativeembodiments, this description is not intended to be construed in alimiting sense. Various modifications and combinations of theillustrative embodiments, as well as other embodiments of the invention,will be apparent to persons skilled in the art upon reference to thedescription. It is therefore intended that the appended claims encompassany such modifications or embodiments.

What is claimed is:
 1. A method for vehicle-to-everything (V2X)communication in a wireless network, the method comprising: determining,by a first User Equipment (UE), a V2X carrier load in a coverage area ofa Base station (BS); and transmitting, by the first UE, a data messageover an air interface using either a random resource selection techniqueor a resource sensing multiple access technique based on the V2X carrierload in the coverage area of the BS.
 2. The method of claim 1, whereinthe air interface is a sidelink connection extending between the firstUE and a second UE.
 3. The method of claim 1, wherein the air interfaceis a wireless connection extending between the first UE and the BS. 4.The method of claim 1, wherein the data message is transmitted over agrant-free resource that is autonomously selected by the first UE. 5.The method of claim 1, wherein the first UE transmits the data messageusing the random resource selection technique when the V2X carrier loadin the coverage area of the BS is less than a lower load threshold orgreater than an upper load threshold.
 6. The method of claim 5, whereinthe first UE transmits the data message using the resource sensingmultiple access technique when the V2X carrier load in the coverage areaof the BS is in-between the lower load threshold and the upper loadthreshold.
 7. The method of claim 6, further comprising: receiving, bythe first UE, at least one of the upper load threshold and the lowerload threshold from the BS.
 8. The method of claim 1, wherein the firstUE senses a grant-free resource for a sensing period prior totransmitting the data message over the grant-free resource when thefirst UE transmits the data message using the resource sensing multipleaccess technique.
 9. The method of claim 8, wherein the first UEtransmits the data message over the grant-free resource prior toexpiration of the sensing period when the first UE transmits the datamessage using the resource sensing multiple access technique.
 10. Themethod of claim 1, wherein determining the V2X carrier load in thecoverage area of the BS comprises: determining the V2X carrier loadaccording to an energy level on one or more sub-carriers associated withthe BS. ii. The method of claim 1, wherein determining the V2X carrierload in the coverage area of the BS comprises: monitoring a controlchannel to determine a number of grant-free transmissions performed byneighboring UEs; and determining the V2X carrier load according to thenumber of grant-free transmissions performed by neighboring UEs.
 12. Amethod for vehicle-to-everything (V2X) communication in a wirelessnetwork, the method comprising: determining, by a first User Equipment(UE), a length of a V2X data message; and transmitting, by the first UE,the V2X data message over an air interface using either a randomresource selection technique or a resource sensing multiple accesstechnique based on the length of the V2X data message.
 13. The method ofclaim 12, wherein the air interface is a sidelink connection extendingbetween the first UE and a second UE.
 14. The method of claim 12,wherein the air interface is a wireless connection extending between thefirst UE and a Base Station (BS).
 15. The method of claim 12, whereinthe V2X data message is transmitted over a grant-free resource that isautonomously selected by the first UE.
 16. The method of claim 12,wherein the first UE transmits the V2X data message over a grant-freeresource using the random resource selection technique when the lengthof the V2X data message is less than a data length threshold.
 17. Themethod of claim 16, wherein the first UE transmits the V2X data messageover the grant-free resource using the resource sensing multiple accesstechnique when the length of the V2X data message is greater than thedata length threshold.
 18. The method of claim 17, further comprising:receiving, by the first UE, the data length threshold.
 19. The method ofclaim 18, wherein the first UE senses a grant-free resource for asensing period prior to transmitting the V2X data message when the firstUE transmits the V2X data message using the resource sensing multipleaccess technique.
 20. The method of claim 19, wherein the first UEtransmits the V2X data message over the grant-free resource prior toexpiration of the sensing period when the first UE transmits the V2Xdata message using the resource sensing multiple access technique.
 21. Amethod for vehicle-to-everything (V2X) communication in a wirelessnetwork, the method comprising: determining, by a Base Station (BS), aV2X carrier load in a coverage area of the BS; determining, by the BS,whether a random resource selection technique or a resource sensingmultiple access technique should be used for transmissions in thecoverage area of the BS based on the V2X carrier load of the coveragearea; and transmitting, by the BS, a control message to at least one UE,the control message instructing the at least one UE to performtransmissions using either the random resource selection technique orthe resource sensing multiple access technique.
 22. The method of claim21, wherein the BS instructs the at least one UE to use the randomresource selection technique when the V2X carrier load of the coveragearea is less than a lower load threshold or greater than an upper loadthreshold.
 23. The method of claim 22, wherein the BS instructs the atleast one UE to use the resource sensing multiple access technique whenthe V2X carrier load of the coverage area is in-between the lower loadthreshold and the upper load threshold.
 24. The method of claim 21,wherein the control message is transmitted directly from the BS to theat least one UE.
 25. The method of claim 21, wherein the control messageis transmitted indirectly from the BS to the at least one UE via anintermediate device.
 26. The method of claim 25, wherein theintermediate device is another BS.
 27. The method of claim 25, whereinthe intermediate device is another UE.